| Coordinates: | 33.5667°N -111.5356°W |
| Country: | United States of America |
| Location: | Maricopa County, Arizona |
| Status: | O |
| Construction Began: | 1928 |
| Opening: | 1930 |
| Owner: | United States Bureau of Reclamation |
| Operator: | Salt River Project |
| Dam Type: | A |
| Dam Height: | 207feet[1] |
| Dam Length: | 1260feet |
| Dam Width Crest: | 8feet |
| Dam Width Base: | 33feet |
| Dam Volume: | 120000cuyd |
| Dam Elevation Crest: | 1533feet |
| Dam Crosses: | Salt River |
| Res Capacity Total: | 73613acre ft |
| Res Catchment: | 6330sqmi |
| Res Surface: | 1260acres[2] |
| Plant Hydraulic Head: | 116feet |
| Plant Operator: | Salt River Project |
| Plant Type: | C |
| Plant Capacity: | 13 MW |
The Stewart Mountain Dam is a concrete thin arch dam located 41 miles northeast of Phoenix, Arizona. The dam is 1260feet long, 207feet high, and was built between 1928 and 1930. The dam includes a 13,000 kilowatt (kW) hydroelectric generating unit that is operated by SRP (Salt River Project), an Arizona public utility. It is primarily operated during the summer months. The dam forms Saguaro Lake as it slows the passage of the Salt River in Maricopa County, Arizona. It was named after a ranch that used to be located nearby known as the Old Stewart Ranch.
A camp was built just below the dam in 1927 to house the construction workers; after the damn's completion it was turned into the Saguaro Lake Guest Ranch.[3]
The dam was listed on the National Register of Historic Places in 2017.